EP1842508A1 - Device for treating a blood circulation conduit and method of preparing this device - Google Patents

Abstract

The device has a endoprosthesis (11) deployable between a retracted state and a dilated state in which the endoprosthesis is liberated from a hollow stent (13). A retaining rod including a hook (35) is movably mounted in the stent between a retaining position of a grommet (45) and a liberation position of the grommet. The rod is displaced from its liberation position toward its retaining position that provokes tightening of a tightening buckle (43) from a deployment configuration of the endoprosthesis toward a maintenance configuration of the endoprosthesis. An independent claim is also included for a method of manufacturing a device.

Description

• un tuteur creux délimitant, au voisinage d'une extrémité distale, au moins une ouverture transversale de retenue ;
• une endoprothèse déployable entre un état rétracté contre une surface latérale du tuteur et un état dilaté dans lequel l'endoprothèse peut être libérée du tuteur ;
• au moins un lien filiforme formant une boucle de serrage ceinturant l'endoprothèse et formant un passant engagé dans le tuteur à travers l'ouverture de retenue ;

la boucle de serrage étant extensible entre une configuration de maintien de l'endoprothèse dans son état rétracté et une configuration de déploiement de l'endoprothèse ; et pour le ou chaque lien filiforme,

• une tige de retenue montée mobile dans le tuteur entre une position de retenue du passant et une position de libération du passant.

The present invention relates to a device for treating a blood circulation conduit of the type comprising:

• a hollow stent delimiting, in the vicinity of a distal end, at least one transverse retaining opening;
• a stent deployable between a retracted state against a lateral surface of the stent and an expanded state in which the stent can be released from the stent;
• at least one filiform link forming a clamping loop surrounding the stent and forming a loop engaged in the stent through the retaining aperture;

the clamping loop being expandable between a holding configuration of the stent in its retracted state and a deployment configuration of the stent; and for the or each filiform link,

• a retaining rod movably mounted in the guard between a holding position of the passer and a release position of the passer.

Such a device is applicable to the release into a blood circulation conduit of stents, of the type commonly referred to as "stent", or endovascular stents comprising a stent and a valve attached to the stent. .

A device of the aforementioned type is described in EP-A-0 707 462 . In this device, a stent is mounted coaxially on two hollow stakes, slidable relative to each other. This stent is maintained in its retracted state by means of two filiform links the belting at its ends. The filiform links are passed respectively into distal and proximal retaining openings provided respectively in one and the other of the stakes. The links are engaged around a retaining pin to hold them in position at their proximal end.

For the release of the stent, the stakes are moved relatively relative to one another so that the distance between the retaining apertures decreases.

The decrease in this distance causes the loosening of the filiform links and consequently the simultaneous deployment of the two ends of the stent.

When the placement of the stent in the blood flow conduit is satisfactory, the filament-shaped retaining rod is removed from the device. The links filiforms are then removed from the stakes and extracted out of the patient's body by sliding them into the stakes.

Given the long length of the filiform links, and their sinuous path in the guardians, the risk of jamming or breaking filiform links during their withdrawal is high. The reliability of the device is therefore reduced.

The object of the invention is therefore to propose a device for treating a blood circulation conduit that can be accurately positioned in the vessel, while having a simple and reliable use.

To this end, the subject of the invention is a treatment device of the aforementioned type, characterized in that the retaining rod comprises at least one retaining hook of the passer, the displacement of the retaining rod from its release position to its holding position causing tightening of the clamping loop from its deployment configuration of the stent to its stent holding configuration.

• le crochet est placé à une extrémité distale de la tige de retenue ;
• le crochet délimite, sur la tige de retenue, un tronçon distal de longueur non nulle et un tronçon proximal, le crochet faisant saillie transversalement par rapport au tronçon distal et au tronçon proximal ;
• l'endoprothèse délimite, pour le ou pour chaque lien filiforme, un passage de guidage du lien filiforme, les extrémités de la boucle de serrage étant engagées dans le passage de guidage ;
• le ou chaque lien filiforme est un brin fermé sur lui-même, le passant étant formé par un prolongement de la boucle de serrage s'étendant à partir du passage de guidage entre les extrémités de la boucle de serrage ;
• le ou chaque lien filiforme est monté à demeure sur l'endoprothèse ;
• le tuteur délimite une ouverture de retenue proximale et une ouverture de retenue distale, le dispositif comprenant, pour chaque ouverture de retenue, une tige de retenue distincte comprenant un crochet de retenue ;
• le tuteur délimite une ouverture de retenue proximale et une ouverture de retenue distale, le dispositif comprenant une tige de retenue commune comprenant un crochet distal et un crochet proximal ;
• l'endoprothèse est montée coaxialement sur le tuteur ;
• le ou chaque lien filiforme est libérable de l'endoprothèse, la tige de retenue comprenant des moyens de retenue d'au moins un tronçon de retenue du lien filiforme distinct du passant, le tronçon étant retenu par les moyens de retenue lorsque le passant est libéré du crochet de retenue, pour permettre le déplacement conjoint du lien filiforme et de la tige de retenue ; et
• le tronçon de retenue du lien filiforme forme un passant auxiliaire engagé dans le tuteur à travers une ouverture de retenue, la tige de retenue comprenant un crochet auxiliaire de retenue du passant auxiliaire s'ouvrant de manière proximale par rapport au crochet de retenue du passant.

The device according to the invention may comprise one or more of the following characteristics, taken separately or in any technically possible combination:

• the hook is placed at a distal end of the retaining rod;
• the hook defines, on the retaining rod, a distal section of non-zero length and a proximal section, the hook protruding transversely with respect to the distal section and the proximal section;
• the endoprosthesis defines, for the or for each filamentary link, a guiding passage of the filiform link, the ends of the clamping loop being engaged in the guide passage;
• the or each filamentary link is a strand closed on itself, the passer being formed by an extension of the clamping loop extending from the guide passage between the ends of the clamping loop;
• the or each filamentary link is permanently mounted on the stent;
• the guard delimits a proximal retaining aperture and a distal retaining aperture, the device comprising, for each retaining aperture, a separate retaining shaft including a retaining hook;
• the guard delimits a proximal retaining aperture and a distal retaining aperture, the device comprising a common retaining shaft comprising a distal hook and a proximal hook;
• the stent is mounted coaxially on the stent;
• the or each filiform link is releasable from the stent, the retaining rod comprising means for retaining at least one retaining section of the filiform tie distinct from the passer, the section being retained by the retaining means when the passer is released the retaining hook, to allow the joint movement of the filamentary link and the retaining rod; and
• the retaining section of the filiform tie forms an auxiliary loop engaged in the guard through a retaining aperture, the retaining rod including an auxiliary auxiliary tie retaining hook opening proximally to the retaining hook of the passer.

• conservation de l'endoprothèse dans son état dilaté, le ou chaque passant étant engagé dans un crochet d'une tige de retenue du passant ;
• déplacement de la tige de retenue depuis sa position de libération vers la position de retenue du passant, pour provoquer le serrage de la boucle de serrage et pour amener l'endoprothèse dans son état rétracté.

The subject of the invention is also a method for preparing a device as described above, prior to its implantation in a blood circulation conduit, characterized in that it comprises the following steps:

• preserving the stent in its expanded state, the or each passer being engaged in a hook of a tie rod;
• moving the retaining rod from its release position to the retaining position of the passer, to cause tightening of the clamping loop and to bring the stent into its retracted state.

• la Figure 1 est une vue en élévation d'un premier dispositif de traitement selon l'invention, l'endoprothèse étant maintenue dans son état rétracté ;
• la Figure 2 est une vue en coupe, prise suivant le plan transversal médian II-II, d'un détail de la Figure 1 ;
• la Figure 3 est une vue analogue à la Figure 1, l'endoprothèse présentant son état dilaté ;
• la Figure 4 est une vue analogue à la Figure 2 de l'endoprothèse de la Figure 3;
• la Figure 5 est une vue en perspective de trois-quarts face de l'endoprothèse du dispositif de la Figure 1 dans son état dilaté ;
• la Figure 6 est une vue analogue à la Figure 2 d'un détail d'un deuxième dispositif de traitement selon l'invention ;
• la Figure 7 est une vue analogue à la Figure 6 d'un troisième dispositif selon l'invention ;
• la Figure 8 est une vue analogue à la Figure 6 d'un quatrième dispositif selon l'invention, l'endoprothèse n'étant pas représentée ; et
• la Figure 9 est une vue analogue à la Figure 5 de l'endoprothèse du dispositif de la Figure 8.

The invention will be better understood on reading the description which follows, given solely by way of example, and with reference to the appended drawings, in which:

• Figure 1 is an elevational view of a first treatment device according to the invention, the stent is maintained in its retracted state;
• Figure 2 is a sectional view, taken along the median transverse plane II-II, of a detail of Figure 1;
• Figure 3 is a view similar to Figure 1, the stent having its expanded state;
• Figure 4 is a view similar to Figure 2 of the stent of Figure 3;
• Figure 5 is a perspective view of three-quarter faces of the stent of the device of Figure 1 in its expanded state;
• Figure 6 is a view similar to Figure 2 of a detail of a second processing device according to the invention;
• Figure 7 is a view similar to Figure 6 of a third device according to the invention;
• Figure 8 is a view similar to Figure 6 of a fourth device according to the invention, the stent not being shown; and
• Figure 9 is a view similar to Figure 5 of the stent of the device of Figure 8.

The treatment device shown in Figures 1 to 5 comprises a tubular stent 11 X-axis X ', mounted coaxially on a single guard 13 and connected to the guard 13 by releasable retaining means.

The stent 11 comprises a tubular stainless steel lattice that has spring properties. Thus, this stent is self-expanding.

This endoprosthesis 11 is for example made by braiding a single wire of a superelastic material, as described in the patent application. European EP-A-0 857 471 .

The lattice of the stent 11 defines, in the vicinity of a distal end 15 of the stent 11, a distal guide passageway 16A of the retaining means, and in the vicinity of a proximal end 17 of the stent 11, a 17A proximal guide passage retaining means.

As illustrated in FIG. 5, each guide passage 16A, 17A is delimited by a mesh of the lattice of the stent. The passages 16A, 17A are situated on the same longitudinal generatrix of the stent 11.

The lattice has at the ends 15, 17 of the stent 11 folded son forming elbows.

The stent 11 internally delimits a blood flow conduit 18 of axis X-X '.

In a variant, the passages 16A, 17A are delimited by rings integral with the lattice and arranged in the duct 18.

As known per se, the stent 11 is capable of deforming spontaneously from a retracted state, in which it has a small diameter (FIG. 1) in an expanded state, in which it has a larger diameter (FIG. dilated state constituting its state of rest.

In the example illustrated in Figures 1 and 2, the guard 13 comprises a hollow flexible metal tube of axis X-X '. The inner diameter of the tube is adapted to thread it onto a thread-like surgical guide (not shown) installed on the patient, prior to the placement of the stent 11 in a blood circulation conduit of this patient.

The guard 13 extends longitudinally in one piece between a distal end 19 intended to be implanted in the blood circulation duct and a proximal end 21 intended to be accessible to a surgeon. The proximal end 21 is located away from the stent 11.

Distal and proximal retaining openings 23A and 23B, offset longitudinally, are formed laterally in the guard 13, in the vicinity of the distal end 19 of the guard 13.

In this example, the openings 23A and 23B are formed on the same side with respect to a median longitudinal plane of the guard 13. The distance separating the distal retaining aperture 23A from the proximal retaining aperture 23B is substantially equal to the length endoprosthesis 11 in its retracted state, taken in a longitudinal direction.

The guard 13 defines at its proximal end 21 a control passage 25 selectively closed by means 27 for locking in position of the retaining means.

The stent retaining means 11 comprise a distal retaining rod 31A and a proximal retaining rod 31B, respectively associated with a distal retaining wire 33A and a proximal retaining wire 33B.

The distal retaining pin 31A and the proximal retaining pin 31B are of similar structures. Similarly, the distal retaining wire 33A and the proximal retaining wire 33B are of similar structures. As a result, only distal retaining wire 33A and distal retaining pin 31A will be described below.

The retaining rod 31A is disposed in the stent 13. The length of the rod 31A is greater than or equal to the distance between the distal retaining aperture 23A and the proximal end 21 of the stent 13.

As illustrated in FIG. 2, the rod 31A includes an end hook 35, an actuating portion 37, and a control portion 39 that protrudes through the control passage 25 at the proximal end 21 of the guard 13. The retaining rod 31A thus has a general shape of butt.

The end hook 35 is located at the distal end of the actuating portion 37. It projects laterally with respect to the actuating portion 37 toward the distal retaining aperture 23A.

The actuating portion 37 is made of a flexible metal rod. It extends into the guardian 13.

The control section 39 extends the actuating portion 37 outside the guard 13, through the control passage 25.

The rod 31A is movable in translation along the axis XX 'of the guard 13, between a distal position of release of the retaining wire 33A shown in FIG. 4, and a proximal position of traction of the retaining wire 33A represented on FIG. Figure 2

In the distal release position, the hook 35 extends substantially opposite the distal retaining aperture 23A. In this position, the control section 39 has a minimum length.

In the proximal traction position, the hook 35 is located between the proximal retaining aperture 23B and the distal retaining aperture 23A. The length of the control section 39 is then maximum.

In the example shown in Figures 1 to 5, the distal retaining wire 33A comprises a single strand of flexible material closed on itself. The distal retaining wire 33A thus forms a clamping loop 43, located outside the guard 13 to surround the stent 11, and a loop 45 engaged in the guard 13 through the distal retaining aperture 23A.

The distal retaining wire 33A is permanently mounted on the stent 11.

The tightening loop 43 surrounds the stent 11 outside the mesh, along a circumference about the X-X 'axis. It extends between a first end and a second end engaged in the proximal guide passage 16A and connected to the guide 45.

Alternatively, the clamping loop 43 is engaged in the lattice of the stent 11, along a circumference, passing successively inside and outside the trellis.

The guide 45 extends into the guard 13 by connecting the two ends of the clamping loop 43 through the retaining opening 23A. The loop 45 is engaged in the hook 35 of the retaining rod 31A.

The clamping loop 43 is extensible between a holding configuration of the stent 11 in its retracted state, and a deployment configuration of the stent 11.

In the holding configuration shown in Figure 2, the diameter of the clamping loop 43 is minimal, while the length of the loop 45 in the guard 13 is maximum.

Conversely, as shown in Figure 4, when the clamping loop 43 occupies its deployment configuration, its diameter is maximum, while the length of the passage 45 in the guard 13 is minimal.

When the tightening loop 43 occupies its holding configuration of the stent 11, the stent 11 is held in its retracted state against the stent 13 along a peripheral side surface of the stent 13. Conversely, when the buckle 43 occupies its deployment configuration, the stent 11 is free to occupy its expanded state.

The operation of the first processing device according to the invention will now be described as an example.

At first, the device is kept in a sterile package (not shown).

In the package, each retaining rod 31 substantially occupies its release position of the loop 45, in which the hook 35 is located opposite a retaining opening 23A, 23B.

For each wire 33A, 33B, the loop 45 remains engaged in an associated hook 35, so that the retaining rod 31A, 31B retains the retaining wire 33A, 33B.

The distal and proximal retaining wires 33A and 33B are engaged around the lattice of the stent 11, so that each clamping loop 43 occupies its deployment configuration. The stent 11 is thus maintained in its expanded state.

This packaging retains the mechanical properties of the stent 11, particularly the tubular lattice thereof is embedded in an extensible and waterproof film, such as an elastomer.

In a second step, the surgeon implants a surgical guide (not shown) circulating in the blood circulation duct or vein from the external introduction point to the area of the vein or artery in which must be implanted the tubular stent 11.

Then, the surgeon extracts the device from its packaging for implantation of the stent 11 into the blood circulation conduit or the vein. The surgeon then releases the locking means 27 of the rods 31A, 31B and pulls on the control sections 39 of the retaining rods 31A, 31B, in order to increase the length of these sections 39.

During this movement, each hook 35 moves towards the proximal end 21 of the guard 13, until the retaining rods 31A, 31B occupy their position of retaining the loop.

During this movement, each retaining rod 31A, 31B pulls on a retaining wire 33A, 33B corresponding. The length of each loop 45 increases, and the diameter of the clamping loops 43 decreases correspondingly. The stent 11 thus passes from its expanded state to its retracted state against a peripheral lateral surface of the guard 13, in which the mesh is substantially in abutment against the guard 13, around this guard 13. The guard 13 is then located in the circulation duct 18.

The surgeon then activates the locking means 27 in position of the retaining rods 31A, 31B to immobilize the rods 31A, 31B with respect to the guard 13.

The stent 11 is thus introduced coaxially with the stent 13 to its place of implantation by displacement along the surgical guide (not shown).

In some cases, and to maintain a minimum radial size, a sheath (not shown) is disposed around the stent 11, before this introduction, and removed once the introduction performed.

Once the stent 11 is introduced, the surgeon proceeds with its deployment.

Depending on the conformation of the blood circulation duct to be treated, he may choose to deploy first or the other of the ends 15 and 17 of the stent 11.

As an example, the deployment of the distal end 15 will be described.

First, the surgeon selectively releases the control portion 39 from the distal retaining pin 31A. Then, it gradually decreases the length of this section 39 by moving the rod 31A towards the distal end 19 of the guard 13, which moves the hook 35 towards the distal end 19.

During this movement, the length of the loop 45 decreases. The diameter of the clamping loop 43 increases correspondingly, which allows the deployment of the stent 11 radially relative to the axis XX 'of the stent 13 at the distal end 15 of the stent 11. The lattice therefore moves away from the guard 13 and approaches the walls P of the duct to be treated to bear against these walls P.

If the surgeon is not satisfied with the positioning of the distal end 15 of the stent 11 when it is deployed, it again actuates the control section 39 by moving the retaining rod 31A towards the proximal end 21 13. This increases the length of the loop 45 and decreases the active length of the clamping loop 43 to compress the stent 11 against the stent 13. The stent 11 is then moved to a more satisfactory position.

Similarly, the surgeon then deploys the proximal end 17 of the stent 11 by means of the proximal retaining wire 33B.

In this configuration, the retaining rods 31A, 31B occupy their position of release of the loop 45. The loops 45, however, remain engaged in the hooks 35.

When the surgeon is satisfied with the positioning of the distal end 15 of the stent 11, he moves the distal retaining rod 31A toward the distal end 19 of the stent 13 to bring the hook 35 past the retaining aperture distal 23A, until the loop 45 is completely released from the hook 35.

The distal end 15 of the stent 11 is then irreversibly fixed to the walls P of the blood circulation conduit.

The surgeon then proceeds for the proximal end 17 of the stent 11. Then, he pulls the stent 13 and the retaining stems 31A, 31B out of the patient. The guard 13 is then completely released from the stent 11.

In this device, the length of the retaining wires 31A, 31B is minimal, so that their circulation in the guard 13 has low risk of blockage.

As a result, the reliability of the deployment of the stent is improved, since it is no longer necessary to circulate long lengths of wire in the guardian 13.

In a variant shown in dashed lines in FIG. 5, each loop 45 has an end ring 101, for example made of a radiopaque material, intended to be gripped by a hook 35.

In the second device according to the invention, shown in Figure 6, the hook 35 of each retaining rod 31A, 31B is not located at the distal end of the rod 31A, 31B.

Thus, each hook 35 defines on the rod 31A, 31B a proximal section 61 and a distal section 63 of non-zero length, adapted to retain the hook 35 in the guard 13. The hook 35 projects radially relative to the proximal section 61 and at the distal portion 63.

When the retaining rod 31A, 31B is placed in its position of release of the loop 45, with the hook 35 located opposite a retaining opening 23A, 23B, the distal section 63 bears against the inner surface 67 of the guard 13 distal to opening 23A, 23B. This prevents the hook 35 from being driven by the passage 45 outside the guard 13 through the retaining opening 23A, 23B during the deployment of the stent 11. The reliability of the device is further improved.

Alternatively (not shown), the two retaining rods 31A, 31B are mechanically connected at a point proximal to the retaining aperture proximal 23B when the hooks 35 are located opposite the retaining openings 23A, 23B.

The third device according to the invention, shown in Figure 7, comprises a single retaining rod 31 provided with a distal retaining hook 35A located at the distal end of the shaft 31, and a proximal retaining hook 35B which protrudes with respect to the rod 31.

The distance separating the distal hook 35A from the proximal hook 35B is substantially equal to the distance between the distal retaining aperture 23A and the proximal retaining aperture 23B.

This third device allows the simultaneous deployment of the proximal end 17 and the distal end 15 of the stent 11.

A fourth device according to the invention is shown in Figures 8 and 9. This device is a variant of the second processing device according to the invention. However, unlike the second device, each retaining wire 33A, 33B is releasable from the endoprosthesis 11.

For this purpose, each retaining wire 33A, 33B forms a main lead 45 connected to a first end of the clamping loop 43, and an auxiliary loop 201 disposed in the guard 13 and connected to a second end of the clamping loop 43 .

The clamping loop 43 is formed by two adjacent strands of the retaining wire 33A, 33B. These two strands are folded in a loop at the first end of the clamping loop 43 to form the main loop 45 and are folded in a loop at the second end of the clamping loop 43 to form the auxiliary loop 201.

The main passer 45 and the auxiliary passer 201 are connected to the clamping loop 43 through the same retainer aperture 23A, 23B and through the same guide passage 16A, 17A.

Unlike the device shown in FIG. 6, each retaining rod 31A, 31B has at its distal end a retaining clip 203 of the auxiliary passer 201.

The clip 203 is formed by a fold 205 of the distal portion 63 of the retaining pin 31A, 31B extending between the distal end of the rod 31A, 31B to a point proximal to the retention hook 35. The fold 205 extends opposite the hook 35 and the retaining opening 23A, 23B, with respect to the axis of the rod 31A, 31B. The clamp 203 opens towards the end proximal 21 of the guardian 13.

The auxiliary passer 201 is engaged in the retaining clip 203.

When the surgeon extracts the fourth device from its package and moves each retaining rod 31A, 31B towards the proximal end 21 of the guard 13. The hook 35 and the clip 203 of each rod 31A, 31B also move toward this end. proximal end.

During this movement, the passer 45 and the auxiliary passer 201 are pulled in the guard 13 towards the proximal end 21 so that the length of the clamping loop 43 decreases to move the stent 11 from its expanded state to its retracted state against the guardian 13.

Then, the deployment of the stent 11 is similar to that of the second treatment device.

When the stent 11 is deployed in position in the blood circulation duct, and the surgeon is satisfied with the positioning of this stent, he moves the retaining rod 31A, 31B towards the distal end 19 of the guard 13 to bring the stent into position. hook 35 beyond the corresponding retaining aperture 23A, 23B. The main passer 45 is then completely free of the hook 35.

However, given the length of the fold 205, the auxiliary loop 201 remains engaged in the clamp 203.

Then, when the surgeon pulls the retaining pin 31A, 31B toward the proximal end 21 of the guard 13, he also pulls on the corresponding retaining wire 33A, 33B through the auxiliary passer 201 engaged in the clip 203 to allow a joint displacement of the retaining wire 33A, 33B and the retaining rod 31A, 31B. The retaining wire 33A, 33B is then released completely from the stent 11, and extracted from the patient at the same time as the retaining rod 31A, 31B.

Claims (12)

A device for treating a blood circulation conduit, of the type comprising: - a hollow stent (13) defining, in the vicinity of a distal end (19), at least one transverse opening (23A, 23B) retaining; - an endoprosthesis (11) deployable between a retracted state against a lateral surface of the stent (13) and an expanded state in which the stent (11) can be released from the stent (13); at least one filamentary link (33A, 33B) forming a clamping loop (43) surrounding the stent (11) and forming a loop (45) engaged in the stent (13) through the retaining opening (23A, 23B);
the clamping loop (43) being expandable between a holding configuration of the stent (11) in its retracted state and a deployment configuration of the stent (11); and for the or each filiform link (33A, 33B), - a retaining rod (31A, 31B) mounted movably in the guard (13) between a retaining position of the loop (45) and a release position of the loop (45); characterized in that the retaining pin (31A, 31B) comprises at least one hook (35) for retaining the pin (45), displacing the retaining pin (31A, 31B) from its release position to its position retainer causing the clamping loop (43) to be tightened from its deployment configuration of the stent (11) to its stent holding configuration (11). Device according to claim 1, characterized in that the hook (35) is placed at a distal end of the retaining rod (31A; 31B). Device according to claim 1, characterized in that the hook (35) delimits, on the retaining rod (31A, 31B), a distal section (63) of non-zero length and a proximal section (61), the hook (35) ) protruding transversely with respect to the distal section (63) and the proximal section (61). Device according to any one of the preceding claims, characterized in that the endoprosthesis (11) defines, for the or for each filiform link (33A, 33B), a passage (16A, 17A) for guiding the filiform link (33A, 33B), the ends of the clamping loop (43) being engaged in the guide passage (16A, 17A). Device according to Claim 4, characterized in that the or each filiform link (33A, 33B) is a strand closed on itself, the loop (45) being formed by an extension of the clamping loop (43) extending from the guide passage (16A, 17A) between the ends of the clamping loop (43). Device according to any one of the preceding claims, characterized in that the or each filamentary link (31A, 31B) is permanently mounted on the stent (11). Device according to any one of the preceding claims, characterized in that the guard (13) delimits a proximal retaining opening (23B) and a distal retaining opening (23A), the device comprising, for each retaining opening (23A, 23B), a separate retaining rod (31A, 31B) comprising a retaining hook (35). Device according to any one of claims 1 to 6, characterized in that the guard (13) defines a proximal retaining opening (23B) and a distal retaining aperture (23A), the device comprising a common retaining rod (31). ) comprising a distal hook (35A) and a proximal hook (35B). Device according to any one of the preceding claims, characterized in that the endoprosthesis (11) is mounted coaxially on the guard (13). Device according to any one of the preceding claims, characterized in that the or each filamentary link (33A, 33B) is releasable from the stent (11), the retaining rod (31A, 31B) comprising means (203) retaining at least one retaining section (201) of the filiform link (33A, 33B) separate from the passer (45), the section (201) being retained by the retaining means (203) when the passer (45) is released from the retaining hook (35), to allow joint movement of the filamentary link (33A, 33B) and the retaining rod (31A, 31B). Device according to claim 10, characterized in that the retaining section (201) of the filiform link (33A, 33B) forms an auxiliary loop engaged in the guard (13) through a retaining opening (23A, 23B), the rod retaining clip comprising an auxiliary hook (203) for retaining the auxiliary passer (201) opening proximally with respect to the retaining hook (35) of the passer (45). Process for the preparation of a device according to any one of the preceding claims, prior to its implantation in a blood circulation conduit, characterized in that it comprises the following steps: (a) storing the stent (11) in its expanded state, the or each passer (45) being engaged in a hook (35) of a retaining rod (31A, 31B) of the loop (45); (b) moving the retaining pin (31A, 31B) from its release position to the holder (45) retaining position to cause the clamping loop (43) to be tightened and to bring the stent ( 11) in its retracted state.

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